First Battle of Cambrai

The First Battle of Cambrai was fought from 20 November to 7 December 1917 on the Western Front of World War I. The British launched an offensive against the German Hindenburg Line in front of Cambrai in France; led by tanks and making innovative use of artillery, the operation achieved a shortlived breakthrough.

Background
The second half of 1917 was a time of setbacks for the Allies on most fronts, but British generals remained committed to the offensive. On the Eastern Front, the failure of Kerensky Offensive in the summer of 1917 was followed by the collapse of the Russian army and the Bolshevik seizure of power. In Italy, the Austro-German breakthrough at Caporetto in late October put the Italian army to flight. On the Western Front, the British front achieved success with an offensive at Messines in June. A British-led offensive at Ypres, at the end of July, resulted in high casualties and small gains, ending with Allies capturing Passchendaele Ridge in early November.

The British were the first to use tanks, during the Battle of the Somme in September 1916. In July 1917, a Tank Corps was formed. Used to support infantry, tanks had proved useful but not decisive. At Third Ypres (Passchendaele), they were often unable to operate on the soft, muddy terrain.

Battle
The proposal for an operation at Cambrai originated with the British Tank Corps. Its commander, Brigadier-General Hugh Elles, and his Chief of Staff Colonel John Fuller were eager to show what tanks could achieve if deployed as a mass shock force rather than scattered among infantry. As tanks easily became bogged down in soft ground, they identified Cambrai, where the land was firm, dry, and chalky, as a suitable location for an attack.

Elles presented the proposal for a tank raid to General Julian Byng, who had commanded the Canadian Corps in the taking of Vimy Ridge in April 1917. As commander of the British 3rd Army from July 1917, Byng was responsible for the Cambrai sector. At the same time, he was approached by a divisional artillery commander, General Hugh Tudor, who wanted to try some new tactics involving artillery. British gunners had been working on ways to achieve accurate "predicted fire." A variety of factors had previously made it impossible to hit distant targets reliably without firing many preliminary ranging shots, which inevitably put the enemy on alert. Tudor believed it was now possible for guns to hit their targets without this "preregistration" and to gain surprise by delaying opening fire until the tanks and infantry were ready to go forward. Dispensing with a prolonged preliminary bombardment also avoided churning up the ground ahead of the tanks.

Attempt at a breakthrough
British commander-in-chief Field Marshal Douglas Haig approved the operation on 13 October. The Cambrai attack had been conceived as a "raid," because the Tank Corps commanders knew their machines were too mechanically unreliable for a sustained offensive. By November, however, it had evolved into an ambitious attempt at a breakthrough, with two cavalry divisions on hand to ride into the open country beyond the German lines. The German defenses in front of Cambrai formed part of the Siegfriedstellung, a sector of the Hindenburg Line to which German troops had withdrawn from the Somme in spring 1917.

Physically the defenses were strong. Barbed wire entanglements hundreds of yards deep fronted three lines of trenches and fortified positions reaching to a depth of 4 miles. But the sector was only lightly garrisoned by two German divisions with very limited support. The British plan depended upon surprise. Tanks and artillery were moved into position at night. Aircraft flew up and down the front to mask the noise of the tank engines. The entire strength of the Tank Corps and 1,000 artillery pieces were in position by 20 November without the Germans realizing it.

A hurricane artillery bombardment began at 6:20 AM, followed by the advance of 300 Mark IV tanks. Clanking forward at walking place, they crushed the German wire and crossed the trenches. Infantry followed, some with their rifles slung over their shoulders and smoking cigarettes. In places there were hardly any British casualties. Some infantry divisions had advanced more than 3 miles by midday.

Generally, the stunned Germans surrendered without a fight. The exception at Flesquieres, in the center of the attack. Here, a German artillery general, Oskar von Watter, ordered his men to roll forward field guns and pick off the tanks as they came over a ridge. With the supporting infantry of the 51st Highland Division too far behind the tanks, 28 tanks were lost and the advance was halted. By the end of the day, some British forces had crossed the St. Quentin Canal and the path into the rear of the German defenses was open, but cavalry failed to exploit the brief opportunity for a breakthrough.

Hollow victory
After the horrors of Passchendaele, the initial success at Cambrai was trumpeted by the British as a victory. But by the end of the first day, 179 tanks were out of action, 65 destroyed by the Germans, and the rest broken down or ditched. Haig insisted that the offensive continue, but it became bogged down in a struggle for Bourlon Wood, 4 miles west of Cambrai. By 30 November, German commanders had moved fresh troops to Cambrai and organized a counteroffensive. The British advance had created a salient. The Germans attacked it from the north and south. They were trying out their own new tactics, using stormtroopers - elite assault forces trained in infiltration tactics. Launched against tired British soldiers insufficiently prepared for defense, the German counterattacks broke through on the southern flank, until halted by the British Guards Disivion. By the end of the first week in December, the battle ewas over. The British retained their hold on one section of the Hindenburg Line but had lost ground elsewhere. The number of casualties was around 45,000 on each side. After the hopes raiised on 20 November, it was another severe disappointment for Britain.

Aftermath
The Battle of Cambrai showed that new technology and tactics were making it possible to overcome even strong defenses on the Western Front. This pointed the way to more mobile warfare. German assault tactics employing stormtroopers created major breakthroughs in their spring offensives in 1918, leaving Cambrai far behind German lines. The Allies returned to Cambrai in October 1918, when it was taken by Canadian troops during the Hundred Days Offensive that ended the war.

British and French tanks played a significant role in Allied operations in 1918. After the war, the Battle of Cambrai became a reference point for military theorists advocating the use of tanks as the primary shock force in modern warfare.